The present invention relates to a new and improved construction of a controlled deflection roll, also referred to as a roll with bending or sag compensation.
Generally, speaking, the controlled deflection roll of the present development is of the type comprising a stationary roll support or core and a roll shell rotatable about the stationary roll support. The roll shell is supported at the roll support by the action of pressure or support elements movable relative to the roll support, bearing at such roll support and effective at the roll shell by exerting a supporting force. The support elements are provided with regulators for influencing their support force.
Controlled deflection rolls of this type are known to the art, for instance, from U.S. Pat. No. 3,802,044, granted Apr. 9, 1974 and U.S. Pat. No. 3,885,283, granted May 27, 1975. With the controlled deflection roll disclosed in the aforementioned U.S. Pat. No. 3,802,044 the roll shell is mounted at its ends at the roll support in roller bearings, whereas in the case of the controlled deflection roll disclosed in the likewise aforementioned U.S. Pat. No. 3,885,283 the roll shell is provided at its ends with guides by means of which the roll shell is movable in relation to the roll support in a press or contact plane where there are effective the support or pressure elements.
If such type of controlled deflection rolls are incorporated into rolling mills, then in the press or pressure-exerting position one of the rolls must assume a fixed position, whereas the other roll or its roll shell must be designed such that it is movable in order to carry out the press or pressure-exerting movements. It is possible for the roll shells of both rolls to act directly upon one another, or there can be arranged between both such rolls a further roll which, as a rule, is usually constituted by a solid roll.
If there are employed rolls having a roll shell rotatably mounted at the roll support, for instance of the type disclosed in U.S. Pat. No. 3,802,044, then there exists the problem that the forces effective at the bearing arrangements, i.e. in the roller bearings located between the roll shell and the roll support, are extremely difficult to determine. There are known from U.S. Pat. No. 4,023,480, granted May 17, 1977 and the Austrian Pat. No. 354,143 analagous devices by means of which it is possible to approximately determine these forces. However, it is not possible to determine with such equipment hysteresis forces and dynamic forces which can assume considerable values.